bluewave

August has had the greatest number of these extreme rainfall events during the 2010's at 7 so far. 8-17-18....4.73...North Merrick 8-18-17....3.80...East Shoreham 8-20-16....3.85...Calverton 8-1-16.....5.34...New Windsor 8-13-14...13.51...Islip 8-15-11...10.20...Lido Beach 8-28-11...8.92....EWR

Were you able to record what your maximum rainfall rate was? I would be curious to know the shortest amount of time for picking up an inch of rain during the event.

Update for Beaufort and Chukchi and Beaufort: The combined Chukchi & Beaufort Seas ice extent from the @NSIDC passive microwave data has fallen rapidly in the past two weeks, and is now about at median for the 2010s. Median date for extent min is Sep14. #Arctic #akwx#seaice @Climatologist49 @ZLabe @DaveSnider @CinderBDT907pic.twitter.com/4Z5wdnl2HD 6:53 AM - 7 Aug 2018

Updated for Rjay in North Merrick with 4.73" on 8-7-18

https://nsidc.org/arcticseaicenews/2018/08/ice-loss-speeds-up-during-second-half-of-july/ Despite finishing ninth lowest in the monthly average, ice loss was rapid during the month. As a result, by July 31 daily extent tracked fourth lowest in the satellite record, just below the extent seen last year at this time, and also just above that seen in 2007, 2011, and 2012.

Following the big reduction in multiyear ice around 2007, the best the Arctic can do during the melt season is 2009 or 2013. NSIDC September average extents above 6 million sq km were common for 1990's and early 2000's. Arctic amplification really took off when the extents regularly dropped below that level.

The dominant summer reverse dipole pattern of the last 6 years is the main thing keeping the September 2012 record out of reach. But even the more favorable summer pressure patterns for retaining sea ice can't get the Arctic back to pre-2007 ice. I continue to believe that scientists in the future will look back on 2007 as the point which the Arctic shifted to a new warmer state. Remember, we didn't need 2012 finishes to set new Arctic high temperature records since then.

Record low sea ice extent for this date on the Atlantic side. Just an amazing heatwave and ridge near Scandinavia. This follows the record Siberian heat back in June. Sea ice extent has dropped to a record low on the Atlantic side of the #Arctic. In other areas, like the Beaufort Sea, melt has been slower. Each line shows one year from 1979 [purple] to 2017 [white]. 2018 is in red. Daily data over the satellite era is from the @NSIDC. pic.twitter.com/QOqDkNlIXw 8:40 AM - 30 Jul 2018 Yesterday's 18z sounding from Sodankylä recorded 500 hPa geopotential height at 5905 m. With the lack of actual sounding climatology, I checked how that reading compares to reanalysis data: 5905 m is the highest Z500 value in the whole N-Scandinavia, in years 1979-2017. #heatwavepic.twitter.com/6i0q4F8Gvi 3:15 AM - 29 Jul 2018 https://www.washingtonpost.com/news/capital-weather-gang/wp/2018/07/17/scorching-scandinavia-record-breaking-heat-hits-norway-finland-and-sweden/?utm_term=.0638647fb0be An intense heat dome has swelled over Scandinavia, pushing temperatures more than 20 degrees above normal and spurring some of the region’s hottest weather ever recorded. Even as far north as the Arctic Circle, the mercury has come close to 90 degrees. http://ak-wx.blogspot.com/ the central part of Arctic Siberia saw a very large and pronounced warm anomaly, and indeed the Siberian warmth was very extreme by historical standards. At the town of Saskylakh at 72°N (nearly the same as Utqiaġvik), the June mean temperature of 60.0°F was more than 5°F above any other June, with data back to 1936, and the month was a remarkable 17.5°F above the 1981-2010 normal.

7-27-18.....3.00" so far at the Staten Island mesonet. http://www.nysmesonet.org/mesonow#?stid=STAT 1 day:3.00″

Another measure of how strong the reverse dipole is this summer. Yesterday's high of 5.2°C in #Iqaluit, Nunavut is coldest on record for July 17. Previous was 5.4°C in 1978. Records kept since 1946. #NUwx #Nunavut #North 5:28 AM - 18 Jul 2018 Alert, Nunavut hit 10°C for the first time of the year yesterday, 2 weeks later than normal (1981-2010). #Arctic #North #Nunavut 5:36 AM - 18 Jul 2018 Yesterday's high of 0.9°C in Resolute, Nunavut is coldest on record for July 21, beating 1.1°C in 1954. Records kept since 1948. #Nunavut #NUwx #Arctic 6:37 AM - 22 Jul 2018

That recent study is a bit of an outlier. http://www.realclimate.org/index.php/archives/2018/07/does-a-slow-amoc-increase-the-rate-of-global-warming/#more-21540

The Arctic circulation pattern since May has been the complete opposite of 2012.

Looks like the CAB may have set a daily record low temperature with the impressive reverse dipole pattern. http://sites.uci.edu/zlabe/arctic-temperatures/

Lowest surface loss in decades for June. The record late snowpack prevented the local shorebirds from nesting this season. after months of a persistent atmospheric circulation pattern, Greenland is having its least surface ice loss in decades while NW Europe has extreme sun and heat... persistent extremes are an expected signature of #climatechange@PolarPortal #ukheatwave twitter.com/severeweatherE…pic.twitter.com/lsXraH5nuK 6:16 AM - 3 Jul 2018 But Churchill Falls (Labrador) saw its coldest June by a 2C margin; the monthly temperature was 6C below normal. Persistent major circulation anomalies are to blame. pic.twitter.com/Iz5QPeXuBr 8:43 AM - 3 Jul 2018 https://www.scientificamerican.com/article/late-snowpack-signals-a-lost-summer-for-greenlands-shorebirds/ Millions of shorebirds descend on the Arctic each year to mate and raise chicks during the tundra’s brief burst of summer. But that burst, which usually begins in mid-June, never arrived this year for eastern Greenland’s shorebirds, a set of ground-nesting species. Instead, a record late snowpack—lingering into July—sealed the birds off from food and nesting sites. Without these key resources avian migrants to the region will not reproduce in 2018, experts say.

Yeah, 2007 to 2012 was a truly historic period for the Arctic. Some people may not appreciate the rarity of locking in that dipole patttern for 6 seasons in a row. https://onlinelibrary.wiley.com/doi/pdf/10.1029/2012GL053268 Thus we can say that a six year run of near one standard deviation negative excursions (2007–2012) is unique in the 63 year record. To further test the significance of the 2007–2012 AD patterns we randomly generated 10,000 time series, each with 63 points to match the observed time series and with a normal distribution without autocorrelation. For this simple calculation, the chance for having five consecutive values with a negative AD of magnitude greater than 1.0 standard deviation units in a sample size of 63 is rare, less than 1 in a 1000. Yeah, it seems like the SPG region cooling south of Greenland since 2012 is the result of an atmospheric circulation change to more low pressure. SST’s in that region we’re near record levels of warmth prior to the abrupt circulation shift leading into the 2013 summer. Maybe there is some mechanism by which salinity changes following the 2007-2012 record melt can lead atmospheric circulation shifts by months or years?

The NAO averaged for May and June was the most positive on record. This is in stark contrast to the 2012 season which had the 2nd lowest on record.

A -500 meter anomaly vortex is about as strong as I can ever remember seeing in July. This pattern produced the heaviest July snow in Barrow since 1963. The NWS in Utqiaġvik (Barrow) reported 2.0" of snow on Saturday, making this the greatest July calendar day snowfall there since July 4, 1963, when there was 2.9" of snow. #akwx @Climatologist49 @CinderBDT907pic.twitter.com/lkmlmCAG8N 3:13 PM - 8 Jul 2018

Probably one of the the best June outcomes the Chukchi can expect in a post 2007 sea ice era. Chukchi Sea ice extent (from @NSIDC passive microwave data) decreased by 13% during June. The good news: this is the lowest percent decline in June since 2008. The bad news: trend is for more June melt: this would have typical in the 1980s. #Arctic #akwx @Climatologist49 @ZLabepic.twitter.com/KzgcbGy5Tb 11:39 AM - 4 Jul 2018

Chuck, the lower NAO in some of the forecasts is a result of more east based blocking closer to Europe. Pattern back closer to the CAB and Beaurfort is actually one of the strongest July reverse dipole patterns we have seen. Notice the best ridging is focused over Siberia. The models actually have near record low 500 mb heights near the Beaufort for this time of year.

What a reversal from 2012. All the coldest departures in the NH were focused near Greenland and Labrador in June. Right around the extreme cold pool south of Greenland with the slowing AMOC. after months of a persistent atmospheric circulation pattern, Greenland is having its least surface ice loss in decades while NW Europe has extreme sun and heat... persistent extremes are an expected signature of #climatechange@PolarPortal #ukheatwave twitter.com/severeweatherE…pic.twitter.com/lsXraH5nuK 6:16 AM - 3 Jul 2018 https://mobile.twitter.com/Climatologist49/status/1013986099335753733/photo/1 But Churchill Falls (Labrador) saw its coldest June by a 2C margin; the monthly temperature was 6C below normal. Persistent major circulation anomalies are to blame. pic.twitter.com/Iz5QPeXuBr 8:43 AM - 3 Jul 2018

The 500 mb height reversal near the Beaufort in June has been as extreme as it gets. 2007 to 2012 featured the highest sustained heights on record for a 6 year period. 2013 to 2018 has seen a dramatic decline in heights with 2013 registering a lowest single year record.

While this has resulted in a slowing of the rate of sea ice decline relative to the 2005-2012 period, it's still at a level well below the typical late 1990's and early 2000's ice. The extreme Arctic amplification and circulation changes began when the September average extents began to regularly fall below 6 million sq km. In 50 to 100 years, that may turn out to be the more significant number than when the Arctic first went technically ice free.

We are moving right back to a reverse dipole pattern in early July. This has been our typical 2013 to 2018 summer pattern. As long as this continues, we may be able to finish September with an NSIDC average extent not too far from 5 million sq km.

A rare colder than normal month in that region in what has been a sea of record warmth. Technical: ongoing cool wx at Utqiaġvik, Alaska is the largest negative departure of the 30-day running daily standardized temp anomaly since late summer 2014. Illustrates nicely the control by sea ice on Arctic coastal air temps. #akwx #Arctic @Climatologist49 @CinderBDT907pic.twitter.com/PK380UAnXW 9:02 AM - 23 Jun 2018 1pm Friday, Utqiaġvik (Barrow) Alaska hits 40F (4C) for the first time this year. This ties with 1955 as the fifth latest “first 40” in the past 98 years. #akwx@Climatologist49 @CinderBDT907 2:21 PM - 22 Jun 2018

Also a pretty impressive slow down in the melt near Alaska for late June. Sea ice extent around Alaska now running close to the long term average for late June, (passive microwave data from @NSIDC). Early melt in the srn Chukchi Sea has stalled farther north and meltout in the Beaufort Sea is only slowly spreading west. #Arctic @akwx @Climatologist49 pic.twitter.com/d3rbwGXJvV 6:58 AM - 25 Jun 2018